Periodontal disease is commonly known as pyorrhea and is the result of bacteria spreading below the gum line, causing teeth and gums to separate forming spaces or pockets. As the disease progress, the pockets become larger and are filled with bacteria and pus, and in time, destruction of the tissue attachment to the teeth and destruction of the supporting bone structure occurs.
In the United States, periodontal disease is the leading cause of tooth loss in adults over 30 years of age. Periodontal disease is usually painless, site specific and goes through periods of exacerbation and remission, making accurate detection and monitoring imperative in the field of dentistry.
Measurement of pocket depth is a primary method for detecting periodontal (gum) disease. It is common knowledge that early detection and periodic measurements at several locations, as many as six per tooth, is necessary to determine if the gingival sulcus (pocket) is enlarging and how fast. There are many instruments used to measure and record the depth of the pocket, such as, for example, the Ward discloses, in U.S. Pat. No. 3,058,225, a periodontal probe having a handle with a protruding sleeve and flexible probe tip that connects directly to a mechanical indicator or indirectly to an electric current indication device located on the probe handle. There are disadvantages with this type of probe. The sleeve is long and difficult to keep clean. Blood and other body fluids can create deposits inside the sleeve, which can interfere with the smooth movement of the probe tip. These deposits tend to become hardened and more of a problem following procedures of heat sterilization. Therefore, it can be helpful to employ a shorter sleeve that is open and easy to clean. Further, the Ward device does not utilize an automatic recording device, but requires the dentist to make all measurements by taking his eyes off the tip and observing the indicator, resulting in lost time. Since there are as many as six measurements per tooth, and the normal mouth has as many as thirty-two teeth, the time lost in taking as many as 192 separate measurements is considerable.
Grenfell et al., disclose a periodontal probe, in U.S. Pat. No. 3,943,914 that has an electrically connected remote recording console that provides a permanent record of the depth of the gingival sulci around a particular tooth. However, the Grenfell et al. probe has a long, rigid, sleeve, which can be difficult to keep clean.
There are several commercially available periodontal probes. For example, The Vine Valley Research Corp. offers a unit that sounds a “beep” when a preset probing force is reached. This unit, originally developed by Dr. Ronald N. Yeaple and disclosed in U.S. Pat. No. 4,340,069, does not electronically measure pocket depth, only probing pressure.
A published article in The Journal of Periodontology, 1980, Vol. 51, No. 5, pp. 298-300, entitled “A Periodontal Probe that Measures to One Tenth Millimeter”, by S. G. Detsch, discusses a probe with a mechanical readout on the handle. It utilizes a caliper attached to a probe tip, where the probe tip slides within a curved sleeve. This probe does have a controlled force and does not provide electronic readout. And, as with other designs, the curved sleeve is long and can be difficult to keep clean.
An article by U. van der Velden and J. K. de Vries that appeared in The Journal of Clinical Periodontology, 1978, Vol. 5, pp. 188-197, entitled “Introduction to a New Periodontal Probe: The Pressure Probe”, discusses the use of air pressure to extend a probe tip that slides within a sleeve. During probing, the tip can intrude from the position of maximum extension at a force determined by the present pressure, until the metal sleeve contacts the gum margin. The pocket depth is read from a millimeter scale on the handle. What is not disclosed is that the probe has a remote readout. Further, the use of air pressure to extend the probe requires an additional machine unit. And, as with the other disclosures, the sleeve is long and can be difficult to keep clean.
Other disclosures include U.S. Pat. No. 4,203,223, granted to Lautenschlager et al., which describes a periodontal probe that provides a constant force and a relatively short sleeve, which is advantageous for cleaning. However, pocket depths must be read visually, as with common probes, because there is no means for automatic reading or measurement.
Ackerman et al., in U.S. Pat. No. 4,665,621, described a periodontal probe with frictional means for limiting probing force, electronic measurement, and a microcomputer for analyzing and displaying the data. Disadvantageously, the probe has a long, curved sleeve, which is difficult to clean. The curved portion of the sleeve adds friction during movement. The probe tip is extended into the gingival sulcus by pressing a control sleeve. This can be inconvenient due to the difficulty of simultaneously sliding a sleeve and positioning the probe tip in the gingival sulcus.
Further, Hirschfeld et al., in U.S. Pat. No. 4,791,940, disclose a periodontal probe that maintains a constant probing force by use of a spring, uses a remote readout, and provides electronic measurements for computer recording. Advantageously, the sleeve is relatively short, stationary, and fairly flexible. The probe also includes a locking button for controlling the probe tip, allowing a dentist to lock the tip in order to probe at forces greater than that provided by the spring. While this probe solved some prior disadvantages, it requires sterilization of the probe tip after each procedure, and did not include a lighting mechanism for viewing the back of the mouth. In addition, the locking button on the top of the probe could be more often inadvertently pressed by the dentist during a probing procedure.
Matoba et al., in U.S. Pat. No. 5,993,209, disclosed a probe in which the sleeve is flexible for easier maneuvering of the probe and the elongated sleeve projects from the hand piece to facilitate cleaning and sterilization. The probe is moved through the slider using a sliding operating member that is energized by a compressed coil spring. There is a disadvantage here because the very long curved sleeve requires a long curved probe which must also be flexible in order slide easily through the curvature of the sleeve yet rigid enough to provide steady force in the pocket. Additionally there is no indication that the probe force can be controlled.
It can be seen that many of the prior art methods and devices used by periodontists to diagnose and assess the progression of the disease do not provide a controlled, standardized way of probing the gingival sulcus, and often result in only crude measurements. Furthermore, the necessity of having to clean and sterilize devices between uses is a hindrance to the speed and efficiency at which patients can be treated. There is a need for better devices and methods of making rapid, accurate measurements in a standardized fashion in order to diagnose and measure the progression of periodontal disease.